[RESEND, V5 0/2] add one regulator used to power up pcie phy

[RESEND, V5 0/2] add one regulator used to power up pcie phy

[Richard Zhu]

Changes v4->v5:
- Refine the commit logs refer to bhelgaas' comments.
- Resend v5 patch-set after CC "devicetree@vger.kernel.org"
in the mail-list.

v4:
https://patchwork.kernel.org/project/linux-pci/patch/1617091701-6444-2-git-send-email-hongxing.zhu@nxp.com/

Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt |  3 +++
drivers/pci/controller/dwc/pci-imx6.c                    | 20 ++++++++++++++++++++
2 files changed, 23 insertions(+)

[RESEND, V5 1/2] dt-bindings: imx6q-pcie: Add "vph-supply" for PHY
[RESEND, V5 2/2] PCI: imx6: Enable PHY internal regulator when

[RESEND, V5 1/2] dt-bindings: imx6q-pcie: Add "vph-supply" for PHY supply voltage

[Richard Zhu]

The i.MX8MQ PCIe PHY can use either a 1.8V or a 3.3V power supply.
Add a "vph-supply" property to indicate which regulator supplies
power for the PHY.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
---
 Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
index de4b2baf91e8..d8971ab99274 100644
--- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
@@ -38,6 +38,9 @@ Optional properties:
   The regulator will be enabled when initializing the PCIe host and
   disabled either as part of the init process or when shutting down the
   host.
+- vph-supply: Should specify the regulator in charge of VPH one of the three
+  PCIe PHY powers. This regulator can be supplied by both 1.8v and 3.3v voltage
+  supplies.
 
 Additional required properties for imx6sx-pcie:
 - clock names: Must include the following additional entries:
-- 
2.17.1

Re: [RESEND, V5 1/2] dt-bindings: imx6q-pcie: Add "vph-supply" for PHY supply voltage

[Rob Herring]

On Fri, 04 Jun 2021 09:47:48 +0800, Richard Zhu wrote:
> The i.MX8MQ PCIe PHY can use either a 1.8V or a 3.3V power supply.
> Add a "vph-supply" property to indicate which regulator supplies
> power for the PHY.
> 
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
> ---
>  Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>

[RESEND, V5 2/2] PCI: imx6: Enable PHY internal regulator when supplied >3V

[Richard Zhu]

The i.MX8MQ PCIe PHY needs 1.8V in default but can be supplied by
either a 1.8V or a 3.3V regulator.

The "vph-supply" DT property tells us which external regulator
supplies the PHY. If that regulator supplies anything over 3V,
enable the PHY's internal 3.3V-to-1.8V regulator.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
---
 drivers/pci/controller/dwc/pci-imx6.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 853ea8e82952..94b43b4ecca1 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -37,6 +37,7 @@
 #define IMX8MQ_GPR_PCIE_REF_USE_PAD		BIT(9)
 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN	BIT(10)
 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE	BIT(11)
+#define IMX8MQ_GPR_PCIE_VREG_BYPASS		BIT(12)
 #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE	GENMASK(11, 8)
 #define IMX8MQ_PCIE2_BASE_ADDR			0x33c00000
 
@@ -80,6 +81,7 @@ struct imx6_pcie {
 	u32			tx_swing_full;
 	u32			tx_swing_low;
 	struct regulator	*vpcie;
+	struct regulator	*vph;
 	void __iomem		*phy_base;
 
 	/* power domain for pcie */
@@ -621,6 +623,17 @@ static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
 				   imx6_pcie_grp_offset(imx6_pcie),
 				   IMX8MQ_GPR_PCIE_REF_USE_PAD,
 				   IMX8MQ_GPR_PCIE_REF_USE_PAD);
+		/*
+		 * Regarding the datasheet, the PCIE_VPH is suggested
+		 * to be 1.8V. If the PCIE_VPH is supplied by 3.3V, the
+		 * VREG_BYPASS should be cleared to zero.
+		 */
+		if (imx6_pcie->vph &&
+		    regulator_get_voltage(imx6_pcie->vph) > 3000000)
+			regmap_update_bits(imx6_pcie->iomuxc_gpr,
+					   imx6_pcie_grp_offset(imx6_pcie),
+					   IMX8MQ_GPR_PCIE_VREG_BYPASS,
+					   0);
 		break;
 	case IMX7D:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
@@ -1130,6 +1143,13 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 		imx6_pcie->vpcie = NULL;
 	}
 
+	imx6_pcie->vph = devm_regulator_get_optional(&pdev->dev, "vph");
+	if (IS_ERR(imx6_pcie->vph)) {
+		if (PTR_ERR(imx6_pcie->vph) != -ENODEV)
+			return PTR_ERR(imx6_pcie->vph);
+		imx6_pcie->vph = NULL;
+	}
+
 	platform_set_drvdata(pdev, imx6_pcie);
 
 	ret = imx6_pcie_attach_pd(dev);
-- 
2.17.1

Re: [RESEND, V5 0/2] add one regulator used to power up pcie phy

[Lorenzo Pieralisi]

On Fri, 4 Jun 2021 09:47:47 +0800, Richard Zhu wrote:
> Changes v4->v5:
> - Refine the commit logs refer to bhelgaas' comments.
> - Resend v5 patch-set after CC "devicetree@vger.kernel.org"
> in the mail-list.
> 
> v4:
> https://patchwork.kernel.org/project/linux-pci/patch/1617091701-6444-2-git-send-email-hongxing.zhu@nxp.com/
> 
> [...]

Applied to pci/imx6, thanks!

[1/2] dt-bindings: imx6q-pcie: Add "vph-supply" for PHY supply voltage
      https://git.kernel.org/lpieralisi/pci/c/6d78fb2ea5
[2/2] PCI: imx6: Enable PHY internal regulator when supplied >3V
      https://git.kernel.org/lpieralisi/pci/c/a9560daaa3

Thanks,
Lorenzo